Gun perforator



Dec. 16, 1941. c. F. TURECHEK 2,266,345

GUN PERFORATOR Filed Feb. 19, 1941 INVENTOR GZ'OEGf ffa/erovm Fzaj l'atente'd Dec. 16,1941

UNITED STATES GUN ranrona'roa George F. Turechek, Los Angeles, Calif.,assignor to Lane-Wells Company Los Angeles, cum, a

corporation of Delaware J Application February 19, 1941, Serial No.379,652

9 Claims. (Cl. 164--0.5)

My invention relates to gunperforators; that is. to devices adapted tobe lowered into well casing for the purpose of firing bulletstherethrough and thereby opening the casing to fluids from thesurrounding formation. Among the objects of my invention are:

First, toprovide a gun perforator wherein an air space initially atatmospheric pressure is associated with the muzzle end of each un unitto absorb partially the gas blast which follows 10 into thecorresponding air chamber and is internally threaded to form a barrelsocket 8. In-

the bullet;

Second, to provide a'gun perforator of this character in which thechamber forming the air space may function as a sample-receiving chamberfor material loosened by the bullet; c

Third, to provide a gun perforator having a plurality of gun units, eachassociated with an air-space or air chamber in which each of the,

gun units are independent, readily removable and adapted to bepreloaded;

Fourth, to provide a gun perforator of this character in which thespacing between the gun units is minimized so that ,for a gun perforatorof given length a maximum number-of gun units may be incorporated; and

I sponding gun bore, the port being somewhat Fifth, toprovide a gunperforator having air spaces or chambers associated with the gun unitswhich are so arranged that gun barrels of maximum length may be providedand which may in 4 corporate expansion-delay disks whereby the mostadvantageous acceleration rate and muzzle velocity of the bullet may beobtained, thereby providing a gun perforator which is particularlyeffective in its operation.

With the above and other objects in view, as

in section to facilitate illustration; and

Figure 2 is a transverse sectional view through 2-2 of Figure 1, on anenlarged scale.

My gun perforatorcomprises a gun body l-in the form of an elongatedcylinder in which are bored a plurality of large laterally directedsockets which may face all in one direction or alternately in oppositedirections, or define a spiral path along the length of the gunperforator body. Each socket forms at its inner end an air chamber 2 andis provided at its outer end with an internal threaded flange 3.Outwardly from each flange 3 the gun body is provided witha transverseslot [embracing the width of the opening to the air chamber. Each socketreceives a 5 closing theair chamber 2.

yed toward the cartridge chamber.

external flange 6 adapted to coact with the threaded internal flan e l.Abutting shoulders are associated with the flanges so that the gun blockmay be: screwed into a sealed connection Outwardly of its flange 8 thebreech block is provided with a toolreceiving end I of polygonal form,the corresponding slot 4 providing clearance around the tool-receivingend.

The inner end of each breech block projects .A gun barrel- I0 isscrew-threaded into eachv barrel socket 8. I The gun barrel l0 projectsinto the air chamber beyond the breech block and is provided with apolygonal tool-receiving muzzle. end ll. Each barrel is provided with acentrally disposed-gun bore l2, the muzzle end of each being adjacentthe inner wall of the corresponding air chamber.

Each air chamber is provided with a bullet port l3 in registry with themuzzle end of the correlarger than the gun bore to provide ampleclearance for the bullet and is initially covered by-a sealing cap, M.The sealing cap may be in the form of a press-fitted dome-shaped sheetmetal member adapted to withstand the external hydrostatic pressure whenthe gun perforator is submerged in a well bore. The muzzle end of thegun barrel terminates in spaced relation with the inner wall .of the airchamber and forms therewith an annular air chamber port ii. In addition,the gun barrel may be provided inwardly from its muzzle end with one ormore auxiliary pressure bleeding ports l6, which communicate between thegun bore and the air chamber. The function of the 'air chamber ports andbleeder ports will be described in more detail hereinafter.

Each gun barrel receives a bullet I! which is preferably secured to anexpansion-delay, disk l8, preferably cup-shaped and fitting the outerend of the cartridge chamber with its rim direct- The disk serves todelay momentarily the discharge of the bullet so as to cause theexplosive pressures in the cartridge chamber to build up, thereby havingthe efiect of increasing the acceleration of the bullet and,consequently, its penetrating power Also, the disk ill, by reason of itsflange or skirt.

restricts the pressure area against the gun barbreech block Swhich isprovided with a threaded rel to the diameter of the cartridge chamber.

Operation of my'gunperiorator is as follows: a

The function oi the disk I8 is more clearly set forth in my previousPatent No. 2,092,294 issued September 7, 1937.

Each, cartridge chamber 9 receives a cartridge it such as'theelectrically ignited type shown in the Lane Patent No. 2,092,317. Theinner end of the cartridge chamber communicates with a small opening inwhich is set a terminal 20 from which extends a lead 2| to the outsideof the breech block. The lead may be in the form' 01' a small gaugeinsulated wire and is preferably surrounded at the outer end of thebreech block with a. sealing plug 22 to prevent the entrance of wellfluids. The lead 2| is bent laterally to flt in a narrow groove 23whichextends radially across the tool-receiving endof the breech block.At oneside of each transverse slot 4 there isformed a small socket whichreceives a suitable connector fitting 24 which is adapted to receive thelead 2| and which forms a terminal for a conductor wire 25. Theconductor wire extends through a hole provided in the gun body into aconductor channel 25' which extends 'longitudinally in the gun body. Twosuch conductor channels may be provided on diametrically opposite sidesof the gun body and are provided with cov-' ers 21;

The several conductors are suitably connected duce the powder pressureagainst the bullet.

Such excesspressure is absorbed in the air chamber rather than againstthe surrounding casing.

Also, it should be pointed out that immediately after the discharge ofthe buliet'the gases cool rapidly so that the pressures in the airchamber drop'to very low value. As a consequence. any material loosenedby the bullet is caused to flow in with the well liquids as they enterthe air chamber,-so that a sample of the formation penetrated by thebullet may be collected.

Various changes and alternate arrangements may be made within the scopeof the appended claims, in which it is my intention to claim all noveltyinherentin the invention as broadly as I ports in said gun body at theinner ends of said sockets registering with the muzzle ends of said gununits, to permit discharge of bullets from said gun units.

withia c ontroller'which maybe in the nature of.

a stepping switch which is, in turn, connected with a single conductorwire provided in the cable from which the gun perforator issuspended,all a as more fully shown inthe Johnston Patent No.

In the present construction'the primary function of the air space andthe ports which communicate therewith is to reduce the powder blastwhich follows the bullet. It has been found, under some circumstances,particularly with certain grades of pipe having a longitudinal grain,that the application of a tremendous powder blast at the time the bulletis penetrating the casing has the effect of splitting the casing aboveand below the bullet hole. This is apparently due to the fact that whilethe casing is under a rupturing pressure by reason of the movement ofthe bullet therethrough, the powder blast exerts a bursting pressureover a limited region around the bullet. This condition obtainsparticularly when the gun perforator is immersed in liquid. Apparentlythe 2. A gun, perforator comprising: a gun body having a plurality oflaterally directed sockets therein; gun units fitting said sockets andhaving laterally directed bores pointing into said sockets; I

discharge ports in said gun body registering with the muzzle ends ofsaid gun units; said gun units defining, with the walls of said sockets,chambers communicating with the muzzle ends of said gun units; andsealing means for said discharge ports to exclude fluids, in which saidgun inertia of the liquid confines the pressure blast and, consequently,increases the unit pressure against the casing.

In this connection, it should be noted that an excess amount of powdermust be used so that a sustained pressure is maintained against thebullet. In other words, the explosive pressures against the bullet whenthe bullet is at the muzzle end of the gun bore are still extremelyhigh. In counter-distinction, the powder pressure hehind a bulletdischarged from a rifle is lowered to a comparatively small percentageof the initial powder pressure by the time the bullet leaves the riflemuzzle. In the gun perforator this sustained pressure is necessary byreason of the very short length of barrel and the necessity of providingthe maximum acceleration of the bullet, so that its muzzle velocity israised to a point suflicient to cause the bullet to penetrate asurrounding well casing. The auxiliary bleeder ports l6 serve to bleedoff the excess powder pressure into the air chamber; however, not to thepoint of removing all of the impelling force. Similarly, the air chamberport l5 functions to further reperforator may be immersed, from saidchambers.

3. A gun perforator comprising: a gun body defining a plurality oflaterally directed sockets; a plurality of gun units, each including abreech block adapted to be secured to the outer margins of a socket, anda gun barrel having a muzzle end directed into said socket; anddischarge ports communicating with the inner ends of said sockets and inregistry with the muzzle ends of said gun barrels; to permit dischargeof bullets from said gun units therethrough.

4. A gun perforator comprising: a gun body defining a plurality oflaterally directed sockets; a plurality of gun units, each including abreech block adapted to be secured to the outer margins of a socket, anda gun barrel directed into said socket; discharge ports communicatingwith said socket and in registry with the muzzle ends of said gun bores;the walls of said sockets being spaced from said gun barrels to defineair chambers; and means for excluding fluids in which the gun perforatormay be immersed, from said chambers.

5. A gun perforator comprising: a plurality of gun units havinglaterally directed gun bores; and means defining a plurality of airchambers positioned in concentric relation with said gun units and incommunication thereof. j 6. A gun perforator comprising: a plurality ofgun units having laterally directed gun bores; a gun body adapted toremovably receive said gun units; and means defining a plurality of airchambers positioned in concentric relation with said gununits and incommunication with the muzzle ends thereof.

7.-A gun perforator comprising: a gun body having a plurality oflaterally directed sockets with the muzzle ends 'a gun body disposedwith their 'muztherein; gun units fitting said sockets and havinglaterally directed bores pointing into said sockets;

discharge ports in said gun body registering with the muzzle ends ofsaid gun units; said gun units defining, with the walls of said sockets,chambers communicating with the muzzle ends of said gun units; sealingmeans for said discharge ports to exclude fluids, in which said gunperforator may be immersed, from said chambers; a bullet andelectrically fired cartridge for each gun unit; and a plurality ofconductors carried by said gun body and electrically connected with saidcartridges.

8. A gun perforator comprising: a gun body defining a plurality oflaterally directed sockets; a plurality of gun units, each including abreech block adapted to be secured to the outer margins of a socket, anda gun barrel directed into said socket; discharge ports communicatingwith said socket and in registry with the muzzle ends of said gun bores;the walls of said sockets being spaced from said gun barrels to defineair chambers; means forexcluding fluids, in which the gun perforator maybe-immersed, from said chambers; a bullet for each gun barrel; anelectrically fired cartridge for each breech block; electrical leadscommunicating with said cartridges and extending from said breechblocks; and conductors carried by said gun body connected with saidleads.

9. A gun perforator comprising: a gun unit having a laterally directedgun barrel; and means defining an annular .chamber surrounding each gunbarrel and communicating with the muzzle end thereof.

GEORGE F. 'I'URECI-IEK.

